This node behaves like Fluid but is applicable on boundaries.

If this node is selected from the Pairs menu, choose the pair on which to apply this condition. A pair has to be created first. See Identity and Contact Pairs in the COMSOL Multiphysics Reference Manual for more details.

The available options for Thin film model are Thermally thin approximation and General. The former is a lumped model that accounts only for tangential temperature gradients (along the film), whereas the latter uses the Extra Dimension tool to account also for the normal gradients of temperature (through the film’s thickness). The second model may be used for the modeling of bearings for example.

This section is only available when the node is added from one of the versions of the Heat Transfer interface (ht). Enter a Film thickness df.

When the node is added from one of the versions of the Heat Transfer in Thin Shells interface (htsh), the shell’s thickness is used instead.

This section is only available when the Thin film model is set to General.

Define the Number of elements used for the discretization of the film’s thickness

Physics Tab with interface as Heat Transfer, Heat Transfer in Solids, Heat Transfer in Fluids, Heat Transfer in Porous Media, Heat Transfer in Building Materials, Bioheat Transfer, Heat Transfer with Surface-to-Surface Radiation or Heat Transfer with Radiation in Participating Media selected:
Boundaries>interface>Thin Film
Pairs>interface>Thin Film

Physics Tab with interface as Heat Transfer in Thin Shells, Heat Transfer in Thin Films or Heat Transfer in Fractures selected:
Boundaries>interface>Thin Film